Boiler and superheater



Nov. 3, 1931. c. F. wlGREN 1,829,885

BOILER AND SUPERHEA-TER Filed April 5, 1930 ATTORNEY 'lraaafedy Nov. 3, 1931 f 1 a pointed- .out yinfthe,;appended claims. 1o nveni',ion,,however,` together rwith further objects. and advantages,-will bestv be runder'-v PATENT 'Y Vperrier;

'11i CLARENCE@ wrennnfor rnaivncx, JRSEY. assIeNoa I ro cran SUPERHEATER Y f l n f QQMrANY, or NEW AYoRvmivrrY.

Bonnin sUrERHEArEn" c l l inventionlrelates to a 4combined boiler andv superheater v andl aims to 1 provideV an arrangementpwhereby a given degree, of

'superheatmay be attainedcwith a compara- '5 .tively compact superheater .arrangement protected' from excessive{temperatures by steam Vgenerating tubes. g

The novel features of# my invention rlae e stood from a detailed' f-description of a specilic arrangement; yembodying myinveng tiongand y such adescriptionwill now be given '15. "oigany illustrative,embodimentof the invent 'f tion portrayed'in the':accompanying.draw-A ingsfin which y y l i Y Figl is avertical elevation 'of aboiler and superheater arrangementyin accordancewitli my;invention,v one side wall jof the boiler i Y Setting 71kellfglf'@.IIIQVBdforpnrposesof illusT c.trum,and.,V l, l Y I y 2fis a fragmentary.detailshowing a'n ``1.1f'alternativerfarrangementpf lthe superheater'. I ,#Thefarrangement illustratedfin the draw- `:.-ings comprises Ya boiler having a horizontal VVcross drum 10 .withfd'owncomer nipples "12 v,*depending therefromand .connecting Iinto Y f f the tops oit7 'vertical fliea'ders 14.` vExtending laterally from headers 14 are tubesfl or1n,y ing atubebanfk whichfcurves' upwardly so K l. thatfthefupper Aends ,of the tubes 16 connect into horizontal; headers 18y under the roof y2O of lthe boiler. Headers 18 are connected toy 35,* the drum. 10by horizontal steam and water.

crjCulatOr nipples 22. v f i Connectinglinto, ther bottoms of vertical headers 14 andextending downwardly ltherefirmaA is asetoshort vertical nipples 24 which connect into the tops 'offanother set of vertical'lieaders'f26. Extending laterallyi fromthe headersy 26'beneaththe`tube bank *16 is a" group of tubesx28l`28 forming aslag screen 11A@ bankr immediately above the furnace chamber 30gg As shown, tube'sy28 are straight and horizontallyinclined and project-'attheir vupper Y ends laterally beyondV the horizontalfprojectienerqv the lieaders'18 fon-bank 28. 'At their'v upperends thetube'sW-2r3.'connect into athird 5?? group of vertical headers 32 fromthe upper f 1 replication mea .epm 5,1930. serrano; 441,851.

farthest' from the headers'14, a chamber 36 isv formed above the upper ends of tubes 28 and between the nipples 34 andthe bank` 16. I have found that such acha'mberfis a` desirable location or 'a superheater. Owing to lthe fact that the chamberis above the slag screen 28, superheater elementsfin such chamber are protected romexcessive temperatures,l but, as'lthe ordinary slag screen bank is notthick7 the gasesleavinglit on its upper sidexhave a considerable temperature7 espe# Cally whenfthe boiler is yoperating at 'high' rating. Asuperheater in chamber 36 theref forefcan be designed with comparatively small heatingsurface for a given degree of superh'eat and capacity;A In the arrange'ment illustrated, a superheater having elements 38 is placed 'in the `chamber 36 and suspended by'hangers 40, 40 from beams in or above the roofpof the boiler. f

It V's' recognized Ias highly desirable that superheater elements should Vbe drainable,

yand I havefo'und that a chamber in the positiongof chamber 36 lendsitself readily to the installation of a drainable superheater. As shown,L the'superheater in chamber 36 has an upper header 42 and a lower header 44, the ends of the elements 38 preferably being connected into the headers 42 and 44 at the bottom and top respectively, to facilitate connection and disconnection of the elements. The

headers 42 and 44 may be conveniently run lhorizontallyl along the outer wall 46 of the boiler at one end thereof. i TheA individualelements 38 extend in zigzag arrangement Abetween the headersY and areso arranged that there is no slope in any ofthe'straight pipe lengths in the direction fromv th'ebottom header 44 to the top header 42 and so that the bends between the straight pipe' lengths avoid all traps for liquid flowing'fromfone of said headers to the other, and are therefore completely drainable.

Al-'V of/ baffle l51A reaching to an uptake 52.y

- valli of thevboiler and'V the endr portions of lelements 38leXtend through wall'46into chain Y lreferab-ly vthe boiler illustrated in the drawings is provided with internal bailing to direct the gases in an eflicient manner over the generator tubesand over the superheater elements-38. As shown, the baffle 48'runs horizontally valongV the top of the slagloank 28 fro1n the^l1eaders,26 to a lpoint approximately in the middlegof` the slag screen bank,

at which point baiiieV 48 iseonnected withY baiile 50 lrunning sharply upward along the outer edge'fofthe tubebank 16 and'assisting in defining the chamber 36. Batlle 50 is terminated .a suiiicient distance below `the-headers l18 to provide ample space yfor thegases Vto ypass around the upper endof suchbale and y .i depending balilejpl runs downwardly from the roof on the other side of .tubes 16 from bale zand roughly-parallel to it'to provide a down vpass through the bank16 on one'side of baille. 51 and an up pass ronthe other side ,By yreason of the fact that no generator tubes'. intersect the space-occupied by superheater`38,7suehelements losea minimum of heat by radiatiomso that Vthesuperhe'ater elepinents can have, a y.minimum heat absorbing v'surface for a `capacity.` f f Y v y .InFigS-l, theheadersVL 42 and 44 for the given Adegree of superheat and superheater )elements are alongside the front ber36. 'lThis arrangementenables thesuper- Y Y heater-'elements toV be ofthe drainableVT type.

Theinventionfis notlimited tothe feature of 'a drainability, however, and in Fig. 2, -I- have Y illustrated 'a fragment 'of a boilervvhiehl will boiler andthe end portions of superheater be understood as indentical with that shown vin Fig. 1.- InFigf2, however,.the headers-'4Z andr441"ri`or the ysuperheaterl elements are show-nk immediately above the roof 20 of the elements 38 entend downwardly... through `roof 20 into Ytherhamb'er 36. K

1.r The combination .with a boiler`-having claim fa. tubegbank-all the-tubes' of vwhich extend j betweenlower verticall headers and upper horizontal headers, :means .for causing ther- -mal circulation 1nV said bank ing laterally therefrom at one end, and means for/,causing a thermal circulation through are .dra-inable.` 1

' whoseA tubes entend between .verticalV headers i i atl one'end and horizontal-headers ,at vthe Y other "end," connections between said headers ,.jsecondbank. t Y. t Y Y, Y 6. 4The combination. 'of a boiler having a j whenV heated, `i; slag screen belowsaid bank Aand projectcirculation of said bank, a slag screen bank below said first mentioned bank and having connections with said Vdrum for completing its thermalV circulation, the connections of said slag bank including elements forming with the upper ends of the tubesof said `rst bank af-chamber above the slag bank, headers on the outside, of said chamberA and superhe'ater elements within said n chamber and'connected to "said outside headers. i

V4. The combination assetforthinv claim 3 and in which the superheater elements are drainable. Y Y

5. The-combination with a boiler having a tube bank-all the tubesgof which extend between Vlower vertical headers andv upper horizontal headers, -saidtubes 'having upturned `portions for connecting with said horizontal headers, means for causing Athermal '85 circulation in said bank when heated, a slag forming with saidV banks achamberjof a ybailieextending along aY portion of the-upper surface of lsaid slag screen bankhanrd;V l running upwardlyitherefrom closeto the upl turned portions of the tubesinsaid'lirst bank aalong the inner 'edge of` said'- chamberfand ,in said chamber above said a superheater horizontal cross drum, a tube bank all of 5 whose tubes extend between verticaliheaders at one end and horizontal headersatfthe other end, said tub/es ,having .upturned Vlportions for-connecting with V'said horiontal headers,` connections VYbetween said headers v and said drum for"` completing the thermal f circulation Hof said bank, a slagjscreenbank' below said''rst mentionedbank and having-v connections with said .drum' ffor completing its thermal circulation, eonnectionslof said y slag bank includingY elements 'forming j with the upper ends of the tubes of saidtirst bank achamber abovethe Vslag bank, a baill'eeX-V tending along a portion of the upper surface of said slag screen bank andl running uprvwardly therefrom close to the upturned ends of said lirstfbank and alongthe inner edge of said chamber, headers on the outside of said chamber, and superheater elements vwithin said chamber and connected top sai'd outside headers. f

7 Thev` combination l,with a i boiler having a set "of substantially horizontal.' and a set Vof substantially,vertical headers, a group of generating tubes connected withVV saidV headers and having Vits tubes turned` upwardly-.at one'endrforconnecting with said hori- Vzontal headers', means for causingathermal l water circulation through V-V said groupV when 'the,grauesheatedfeddihs a delegan@ circulator nipples connecting said headers.

r and drum, a Vslag screen bankfbelow said group and extending beyond the upturned ends ofthe tubes of said group at one .end

of the boiler, and circulators connecting said -slag bank and said headers, ofv al superheater Y above the extended portion ofsaid slag screen,

and baffling forlcausing hot gases to passy e upwardly through saidl screennand over said i superheater and then over the upturne'dends of- Said. group. A CLARENCE F. WIGREN. 

